Monthly Archives: May 2008

bent button

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So at work yesterday we got a button. All it is, is a big purple Yahoo button that someone got for free. You press the button and it plays Yahooooo really loud. Pretty boring. I figured I would open it up and show people how to smash their fingers on the resistors to change the pitch.

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So I unscrewed the thing and took a look. Pretty simple thing, of course the IC chip is a COB item underneath a blob of epoxy. This makes it really hard to figure out fun things. Someone then pointed out that there seemed to be a little 3 pin socket on the bottom of the thing. As I stared at the thing I saw that one of the pins was labeled Rec. Hmmm, I wondered if it would be possible to re-record the button to be even more obnoxious. I took a couple minutes and inspected the rest of the pins. I had two pins going to the switch to make the thing play. I had a Pl pin that if I jammed a wire between it and the positive power supply it would play. Alright Pl pin is a Play pin. It plays as long as you pull the pin high. There was the Rec pin, an IC pin a GND pin, two pins for the speaker and then a pin going to the resistor.

We sat for a while jamming wires on things and pressing our fingers on the resistor annoying everyone in the office. Then I finally tried connecting the Rec pin to the positive rail. Oops no more Yahooooo sound. I figured I blew something up. But wait I realized there was no more Yahoo but just a hissing. The I realized that the IC pin had a hidden letter and was really a Mic pin. Aha, I’m an idiot, so this turns out to be just a little 10 second recorder chip. All you need to do is pull the Rec pin high and input a mic or something else to the Mic pin and it will record.

We quickly cut up a mini jack cord, plugged it into my iPod and then touched the Rec pin to the power pin and it worked, kinda. It was way to quiet. I realized that I would need to bring the thing home and solder some proper wires to it in order to get good clear connections for recording. So I came home and started tweaking. First thing I did was reconnect the switch to the Play pin, this way when someone hit the button it would only play as long as the button was held down. Seemed like a good way to keep it less annoying if someone recorded something long. Second thing I did was to splice in a button between the Rec pin and the power supply. This way I didn’t have to hold some wire every time I wanted to record. Then I connected a mini jack connector to the Mic pin so it would be easier to record things. The final step was to take the Dremel and make some holes for the new input jack and button

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It came out pretty good. The only problem was the button didn’t hot glue to the case very well. So I ended up just keeping it outside the case until I get something better to attach it. The only thing left that would be cool to do would be to get a decent variable resistor so you can mess with the pitch while holding the button. Over all, a fun little project for the night.

busy days of spring

So I haven’t posted anything lately. And all in all I haven’t really finished any projects lately yet either. I haven’t made any headway on the frequency counter because I haven’t bought the parts I need. I did manage to snag some awesome old Atari joysticks at a church rummage sale. The plan is to convert them to wireless so they can control other things. Last week I attended TI Tech Days 2008. It was a good event. I didn’t pay anything because Digikey sent me a “don’t pay for this event” coupon in the email. They had some good talks on Zigbee and charging lithium ion batteries. I ordered up a neat like 40 dollar TI wireless dev kit that consists of a MSP430 chip and a CC2500 chip. I’m hoping that I can use those for the wireless Atari joy sticks. Also I’ve started building another robot.

J-R the Robot

My daughter has named him J-R. Couple things about him. His body is made of 1/16 inch aluminum, which sucks to cut and drill and bend when all you have is a hack saw, power drill and a counter edge. I went and picked up the aluminum pieces this weekend and since I’m sorta measurement retarded was surprised and how thick it was. Also there’s a couple parts made out of 1/4 inch aluminum bar and this time I was surprised at how small it was. I had to make the parts a couple times over because it was so tiny and the drill holes kept getting messed up. Overall he looks pretty good, not so straight, but straight enough. I have to get a Tamiya dual motor setup and a Sharp GP2D12 infrared sensor and then a bunch of various other components. I’m hoping I’ll be able to wire him up in the next month and then start programming.

Anyway, hopefully in the coming months I’ll get some more projects finished. So stay tuned